1. Field of the Invention
The present invention relates to a lever support structure for a lever-type connector which can be connected by use of the leverage of a lever.
2. Description of the Prior Art
The lever-type connector is advantageous in that the connection and removal thereof can be executed with a small force and, especially, it is often applied to a multipole connector which has 20 poles or more. The basic principle of the lever-type connector utilizes the leverage action of a lever and, as a structure for the lever-type connector, for example, there is known such a structure as shown in FIG. 7. On the left in FIG. 7, there is shown a female connector housing 1 which stores therein a large number of female terminals (not shown), while on the right there is shown a male connector housing 2 which stores therein a large number of male terminals and includes a hood portion 2a for receiving the female connector housing 1. While cam receiving pins 3 are respectively provided on the right and left side wall portions of the female connector housing 1, on the right and left side walls of a hood portion 2a of the male connector housing 2, there are formed slits 4 respectively for receiving the cam receiving pins 3.
Also, a U-shaped lever 5 is rotatably mounted to the male connector housing 2. A structure for mounting the lever 5 to the male connector housing 2 is arranged such that a pair of lever support shafts 2b are projected from the right and left wall portions of the male connector housing 2, two circular bearing holes 5a are respectively formed in the right and left side portions of the lever 5 and, as shown in FIG. 7, the lever support shafts 2b are inserted through the two bearing holes 5a of the lever 5, respectively.
On the back surface of the lever 5, there are formed two cam grooves 6 which are respectively engageable with the cam receiving pins 3. The cam grooves 6 are connected in communication with slits 4 when the lever 5 is held at such position as shown in FIG. 7. If the female connector housing 1 is inserted into the hood portion 2a of the male connector housing 2 and the lever 5 is rotated in a direction of an arrow shown in FIG. 7, then the cam grooves 6 of the lever 5 allows the cam receiving pins 3 and thus the female connector housing 1 to advance deeply into the hood portion 2a of the male connector housing 2, which completes the connection between the male and female connectors.
Now, in the process that the female connector housing 1 is moved into the hood portion 2a by turning the lever 5, due to the mutual fitting between the male and female terminals (not shown), an insertion load is applied to the operation of the lever 5. The insertion load increases as the turn of the lever advances. The operation force necessary to push the operation portion 5b of the lever 5 is increased in opposition to the increase in the insertion load. The increased operation force causes the operation portion 5b of the lever 5 to be flexed in a recessed manner, so that the arms 5c of the lever 5 are respectively extended outwardly. If the arms 5c are extended outwardly too much, then the arms 5c can be removed out of the lever support shaft 2b. As a countermeasure against such removal of the arms 5c, for example, there is known a technique in which a pair of right and left guide walls 7 are provided in the lower portion of the lever 5 of the male connector housing 2 so as to prevent the arms 5c from being widened outwardly when it is turned.
However, in the technique using the guide walls 7, since the width of the male connector housing 2 is increased by the widths of the guide walls 7, the whole structure of the connector housing becomes large in size.
Also, there is available a technique in which removal preventive washers are respectively mounted on the ends of the lever support shafts 2b. However, this technique increases the number of parts and also worsens the connector assembling operability.